|
KOPB-TV
KOPB-TV (channel 10) is a Public Broadcasting Service (PBS) network affiliate#Member stations, member television station in Portland, Oregon, United States, owned by Oregon Public Broadcasting. History KOPB-TV originally signed on the air as KOAP-TV, on February 6, 1961."Educational TV Wins Good Opening Response". (February 7, 1961). ''The Oregonian'', p. 9. The call sign letters stood for "Oregon Agricultural Portland", preceded by the Call signs in North America, K prefix the Federal Communications Commission uses when assigning call signs for stations west of the Mississippi River.Swing, William (February 5, 1961). "Portland To Get First Glimpse Of Educational TV Monday". ''The Oregonian, The Sunday Oregonian'', p. 33. It was a sister station to KOAC-TV in Corvallis, Oregon, whose call letterscarried over from KOAC-AM, which received them in the mid-1920s during its early years broadcasting as an AM radio stationstood for "Oregon Agricultural College" (Oregon State University's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oregon Public Broadcasting
Oregon Public Broadcasting (OPB) is the primary television and radio public broadcasting network for most of the U.S. state of Oregon as well as southern Washington. OPB consists of five full-power television stations, dozens of VHF or UHF translators, and over 20 radio stations and frequencies. Broadcasts include local and regional programming as well as television programs from the Public Broadcasting Service (PBS) and American Public Television (APT), and radio programs from National Public Radio (NPR), American Public Media (APM), Public Radio Exchange (PRX), and the BBC World Service, among other distributors. Its headquarters and television studios are located in Portland. OPB is also a major producer of television programming for national broadcast on PBS and Create through distributors like APT, with shows such as ''History Detectives'', ''Barbecue America'', ''Foreign Exchange'', ''Rick Steves' Europe'', and travel shows hosted by Art Wolfe. , OPB had over one millio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PBS Kids
PBS Kids is the brand for most of the children's programming aired by the Public Broadcasting Service (PBS) in the United States. Some public television children's programs are not produced by PBS member stations or transmitted by PBS. Instead, they are produced by independent public television distributors such as American Public Television, and are not labeled as "PBS Kids" programming, as it is mainly a programming block branding. The target audience is children between the ages of 2 and 8. The network is also available in sub-Saharan Africa and Australia. History PTV block PBS had historically aired programs for children such as ''Sesame Street'', ''Mister Rogers' Neighborhood'', and ''Reading Rainbow''; prior to 1993, these programs aired under general PBS branding. In August 1993, PBS introduced new branding for their children's programs featuring "The P-Pals", animated characters shaped like PBS logos who encouraged skills such as gathering information, self-esteem, co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Very High Frequency
Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves ( radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF). VHF radio waves propagate mainly by line-of-sight, so they are blocked by hills and mountains, although due to refraction they can travel somewhat beyond the visual horizon out to about 160 km (100 miles). Common uses for radio waves in the VHF band are Digital Audio Broadcasting (DAB) and FM radio broadcasting, television broadcasting, two-way land mobile radio systems (emergency, business, private use and military), long range data communication up to several tens of kilometers with radio modems, amateur radio, and marine communications. Air traffic control communications and air navigation systems (e.g. VOR and ILS) wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Height Above Average Terrain
Height above average terrain (HAAT), or (less popularly) effective height above average terrain (EHAAT), is the vertical position of an antenna site is above the surrounding landscape. HAAT is used extensively in FM radio and television, as it is more important than effective radiated power (ERP) in determining the range of broadcasts ( VHF and UHF in particular, as they are line of sight transmissions). For international coordination, it is officially measured in meters, even by the Federal Communications Commission in the United States, as Canada and Mexico have extensive border zones where stations can be received on either side of the international boundaries. Stations that want to increase above a certain HAAT must reduce their power accordingly, based on the maximum distance their station class is allowed to cover (see List of North American broadcast station classes for more information on this). The FCC procedure to calculate HAAT is: from the proposed or actual antenna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effective Radiated Power
Effective radiated power (ERP), synonymous with equivalent radiated power, is an IEEE standardized definition of directional radio frequency (RF) power, such as that emitted by a radio transmitter. It is the total power in watts that would have to be radiated by a half-wave dipole antenna to give the same radiation intensity (signal strength or power flux density in watts per square meter) as the actual source antenna at a distant receiver located in the direction of the antenna's strongest beam (main lobe). ERP measures the combination of the power emitted by the transmitter and the ability of the antenna to direct that power in a given direction. It is equal to the input power to the antenna multiplied by the gain of the antenna. It is used in electronics and telecommunications, particularly in broadcasting to quantify the apparent power of a broadcasting station experienced by listeners in its reception area. An alternate parameter that measures the same thing is effec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
480i
480i is the video mode used for standard-definition digital television in the Caribbean, Japan, South Korea, Taiwan, Philippines, Laos, Western Sahara, and most of the Americas (with the exception of Argentina, Paraguay, and Uruguay). The ''480'' identifies a vertical resolution of 480 lines, and the ''i'' identifies it as an interlaced resolution. The field rate, which is 60 Hz (or 59.94 Hz when used with NTSC color), is sometimes included when identifying the video mode, i.e. 480i60; another notation, endorsed by both the International Telecommunication Union in BT.601 and SMPTE in SMPTE 259M, includes the frame rate, as in 480i/30. The other common standard definition digital standard, used in the rest of the world, is 576i. It originated from the need for a standard to digitize analog TV (defined in BT.601) and is now used for digital TV broadcasts and home appliances such as game consoles and DVD disc players. Although related, it should not be confused with the an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1080i
1080i (also known as Full HD or BT.709) is a combination of frame resolution and scan type. 1080i is used in high-definition television (HDTV) and high-definition video. The number "1080" refers to the number of horizontal lines on the screen. The "i" is an abbreviation for "interlaced"; this indicates that only the even lines, then the odd lines of each frame (each image called a video field) are drawn alternately, so that only half the number of actual image frames are used to produce video. A related display resolution is 1080p, which also has 1080 lines of resolution; the "p" refers to progressive scan, which indicates that the lines of resolution for each frame are "drawn" on the screen in sequence. The term assumes a widescreen aspect ratio of 16:9 (a rectangular TV that is wider than it is tall), so the 1080 lines of vertical resolution implies 1920 columns of horizontal resolution, or 1920 pixels × 1080 lines. A 1920 pixels × 1080 lines screen has a total of 2.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspect Ratio (image)
The aspect ratio of an image is the ratio of its width to its height, and is expressed with two numbers separated by a colon, such as ''16:9'', sixteen-to-nine. For the ''x'':''y'' aspect ratio, the image is ''x'' units wide and ''y'' units high. Common aspect ratios are 1.85:1 and 2.39:1 in cinematography, 4:3 and 16:9 in television photography, and 3:2 in still photography. Some common examples The common film aspect ratios used in cinemas are 1.85:1 and 2.39:1.The 2.39:1 ratio is commonly labeled 2.40:1, e.g., in the American Society of Cinematographers' ''American Cinematographer Manual'' (Many widescreen films before the 1970 SMPTE revision used 2.35:1). Two common videographic aspect ratios are 4:3 (1.:1), the universal video format of the 20th century, and 16:9 (1.:1), universal for high-definition television and European digital television. Other cinema and video aspect ratios exist, but are used infrequently. In still camera photography, the most common aspect ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Display Resolution
The display resolution or display modes of a digital television, computer monitor or display device is the number of distinct pixels in each dimension that can be displayed. It can be an ambiguous term especially as the displayed resolution is controlled by different factors in cathode ray tube (CRT) displays, flat-panel displays (including liquid-crystal displays) and projection displays using fixed picture-element (pixel) arrays. It is usually quoted as ', with the units in pixels: for example, ' means the width is 1024 pixels and the height is 768 pixels. This example would normally be spoken as "ten twenty-four by seven sixty-eight" or "ten twenty-four by seven six eight". One use of the term ''display resolution'' applies to fixed-pixel-array displays such as plasma display panels (PDP), liquid-crystal displays (LCD), Digital Light Processing (DLP) projectors, OLED displays, and similar technologies, and is simply the physical number of columns and rows of pixels creating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Subchannel
In broadcasting, digital subchannels are a method of transmitting more than one independent program stream simultaneously from the same digital radio or television station on the same radio frequency channel. This is done by using data compression techniques to reduce the size of each individual program stream, and multiplexing to combine them into a single signal. The practice is sometimes called "multicasting". ATSC television United States The ATSC digital television standard used in the United States supports multiple program streams over-the-air, allowing television stations to transmit one or more subchannels over a single digital signal. A virtual channel numbering scheme distinguishes broadcast subchannels by appending the television channel number with a period digit (".xx"). Simultaneously, the suffix indicates that a television station offers additional programming streams. By convention, the suffix position ".1" is normally used to refer to the station's main digi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplex (TV)
A multiplex or mux (called virtual sub-channel in the United States and Canada, and bouquet in France) is a grouping of program services as interleaved data packets for broadcast over a network or modulated multiplexed medium. The program services are split out at the receiving end. In the United Kingdom, a terrestrial ''multiplex'' (usually abbreviated ''mux'') has a fixed bandwidth of 8 MHz CODFM of interleaved H.222 packets containing a number of ''channels''. In the United States, a similar arrangement using 6 MHz 8VSB is often described as a ''channel'' with ''virtual sub-channels''. Pay television multiplexes In regards to television, the term multiplex is often used to refer to a single broadcaster offering multiple channels of programming as a single bundle to its subscribers. The term is most synonymous with premium television services, such as those devoted to films (where the term evokes the symbolism of multiplex cinemas) or sports; for instance, film services may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HDTV
High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the generation following standard-definition television (SDTV), often abbreviated to HDTV or HD-TV. It is the current de facto standard video format used in most broadcasts: terrestrial broadcast television, cable television, satellite television and Blu-ray Discs. Formats HDTV may be transmitted in various formats: * 720p (1280 horizontal pixels × 720 lines): 921,600 pixels * 1080i (1920×1080) interlaced scan: 1,036,800 pixels (~1.04 MP). * 1080p (1920×1080) progressive scan: 2,073,600 pixels (~2.07 MP). ** Some countries also use a non-standard CEA resolution, such as 1440×1080i: 777,600 pixels (~0.78 MP) per field or 1,555,200 pixels (~1.56 MP) per frame When transmitted at two megapixels per frame, HDTV provides about five times a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Oregon Public Broadcasting")
